| /* Exception (throw catch) mechanism, for GDB, the GNU debugger. |
| |
| Copyright (C) 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, |
| 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 |
| Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| |
| #ifndef EXCEPTIONS_H |
| #define EXCEPTIONS_H |
| |
| #include "ui-out.h" |
| #include <setjmp.h> |
| |
| /* Reasons for calling throw_exceptions(). NOTE: all reason values |
| must be less than zero. enum value 0 is reserved for internal use |
| as the return value from an initial setjmp(). The function |
| catch_exceptions() reserves values >= 0 as legal results from its |
| wrapped function. */ |
| |
| enum return_reason |
| { |
| /* User interrupt. */ |
| RETURN_QUIT = -2, |
| /* Any other error. */ |
| RETURN_ERROR |
| }; |
| |
| #define RETURN_MASK(reason) (1 << (int)(-reason)) |
| #define RETURN_MASK_QUIT RETURN_MASK (RETURN_QUIT) |
| #define RETURN_MASK_ERROR RETURN_MASK (RETURN_ERROR) |
| #define RETURN_MASK_ALL (RETURN_MASK_QUIT | RETURN_MASK_ERROR) |
| typedef int return_mask; |
| |
| /* Describe all exceptions. */ |
| |
| enum errors { |
| GDB_NO_ERROR, |
| /* Any generic error, the corresponding text is in |
| exception.message. */ |
| GENERIC_ERROR, |
| NOT_FOUND_ERROR, |
| |
| /* Thread library lacks support necessary for finding thread local |
| storage. */ |
| TLS_NO_LIBRARY_SUPPORT_ERROR, |
| |
| /* Load module not found while attempting to find thread local storage. */ |
| TLS_LOAD_MODULE_NOT_FOUND_ERROR, |
| |
| /* Thread local storage has not been allocated yet. */ |
| TLS_NOT_ALLOCATED_YET_ERROR, |
| |
| /* Something else went wrong while attempting to find thread local |
| storage. The ``struct gdb_exception'' message field provides |
| more detail. */ |
| TLS_GENERIC_ERROR, |
| |
| /* Problem parsing an XML document. */ |
| XML_PARSE_ERROR, |
| |
| /* Add more errors here. */ |
| NR_ERRORS |
| }; |
| |
| struct gdb_exception |
| { |
| enum return_reason reason; |
| enum errors error; |
| const char *message; |
| }; |
| |
| /* A pre-defined non-exception. */ |
| extern const struct gdb_exception exception_none; |
| |
| /* Wrap set/long jmp so that it's more portable (internal to |
| exceptions). */ |
| |
| #if defined(HAVE_SIGSETJMP) |
| #define EXCEPTIONS_SIGJMP_BUF sigjmp_buf |
| #define EXCEPTIONS_SIGSETJMP(buf) sigsetjmp((buf), 1) |
| #define EXCEPTIONS_SIGLONGJMP(buf,val) siglongjmp((buf), (val)) |
| #else |
| #define EXCEPTIONS_SIGJMP_BUF jmp_buf |
| #define EXCEPTIONS_SIGSETJMP(buf) setjmp(buf) |
| #define EXCEPTIONS_SIGLONGJMP(buf,val) longjmp((buf), (val)) |
| #endif |
| |
| /* Functions to drive the exceptions state m/c (internal to |
| exceptions). */ |
| EXCEPTIONS_SIGJMP_BUF *exceptions_state_mc_init (struct ui_out *func_uiout, |
| volatile struct gdb_exception * |
| exception, |
| return_mask mask); |
| int exceptions_state_mc_action_iter (void); |
| int exceptions_state_mc_action_iter_1 (void); |
| |
| /* Macro to wrap up standard try/catch behavior. |
| |
| The double loop lets us correctly handle code "break"ing out of the |
| try catch block. (It works as the "break" only exits the inner |
| "while" loop, the outer for loop detects this handling it |
| correctly.) Of course "return" and "goto" are not so lucky. |
| |
| For instance: |
| |
| *INDENT-OFF* |
| |
| volatile struct gdb_exception e; |
| TRY_CATCH (e, RETURN_MASK_ERROR) |
| { |
| } |
| switch (e.reason) |
| { |
| case RETURN_ERROR: ... |
| } |
| |
| */ |
| |
| #define TRY_CATCH(EXCEPTION,MASK) \ |
| { \ |
| EXCEPTIONS_SIGJMP_BUF *buf = \ |
| exceptions_state_mc_init (uiout, &(EXCEPTION), (MASK)); \ |
| EXCEPTIONS_SIGSETJMP (*buf); \ |
| } \ |
| while (exceptions_state_mc_action_iter ()) \ |
| while (exceptions_state_mc_action_iter_1 ()) |
| |
| /* *INDENT-ON* */ |
| |
| |
| /* If E is an exception, print it's error message on the specified |
| stream. for _fprintf, prefix the message with PREFIX... */ |
| extern void exception_print (struct ui_file *file, struct gdb_exception e); |
| extern void exception_fprintf (struct ui_file *file, struct gdb_exception e, |
| const char *prefix, |
| ...) ATTR_FORMAT (printf, 3, 4); |
| |
| /* Throw an exception (as described by "struct gdb_exception"). Will |
| execute a LONG JUMP to the inner most containing exception handler |
| established using catch_exceptions() (or similar). |
| |
| Code normally throws an exception using error() et.al. For various |
| reaons, GDB also contains code that throws an exception directly. |
| For instance, the remote*.c targets contain CNTRL-C signal handlers |
| that propogate the QUIT event up the exception chain. ``This could |
| be a good thing or a dangerous thing.'' -- the Existential |
| Wombat. */ |
| |
| extern NORETURN void throw_exception (struct gdb_exception exception) ATTR_NORETURN; |
| extern NORETURN void throw_verror (enum errors, const char *fmt, va_list ap) |
| ATTR_NORETURN ATTR_FORMAT (printf, 2, 0); |
| extern NORETURN void throw_vfatal (const char *fmt, va_list ap) |
| ATTR_NORETURN ATTR_FORMAT (printf, 1, 0); |
| extern NORETURN void throw_error (enum errors error, const char *fmt, |
| ...) ATTR_NORETURN ATTR_FORMAT (printf, 2, 3); |
| |
| /* Instead of deprecated_throw_reason, code should use catch_exception |
| and throw_exception. */ |
| extern NORETURN void deprecated_throw_reason (enum return_reason reason) ATTR_NORETURN; |
| |
| /* Call FUNC(UIOUT, FUNC_ARGS) but wrapped within an exception |
| handler. If an exception (enum return_reason) is thrown using |
| throw_exception() than all cleanups installed since |
| catch_exceptions() was entered are invoked, the (-ve) exception |
| value is then returned by catch_exceptions. If FUNC() returns |
| normally (with a postive or zero return value) then that value is |
| returned by catch_exceptions(). It is an internal_error() for |
| FUNC() to return a negative value. |
| |
| For the period of the FUNC() call: UIOUT is installed as the output |
| builder; ERRSTRING is installed as the error/quit message; and a |
| new cleanup_chain is established. The old values are restored |
| before catch_exceptions() returns. |
| |
| The variant catch_exceptions_with_msg() is the same as |
| catch_exceptions() but adds the ability to return an allocated |
| copy of the gdb error message. This is used when a silent error is |
| issued and the caller wants to manually issue the error message. |
| |
| FIXME; cagney/2001-08-13: The need to override the global UIOUT |
| builder variable should just go away. |
| |
| This function superseeds catch_errors(). |
| |
| This function uses SETJMP() and LONGJUMP(). */ |
| |
| struct ui_out; |
| typedef int (catch_exceptions_ftype) (struct ui_out *ui_out, void *args); |
| extern int catch_exceptions (struct ui_out *uiout, |
| catch_exceptions_ftype *func, void *func_args, |
| return_mask mask); |
| typedef void (catch_exception_ftype) (struct ui_out *ui_out, void *args); |
| extern int catch_exceptions_with_msg (struct ui_out *uiout, |
| catch_exceptions_ftype *func, |
| void *func_args, |
| char **gdberrmsg, |
| return_mask mask); |
| |
| /* This function, in addition, suppresses the printing of the captured |
| error message. It's up to the client to print it. */ |
| |
| extern struct gdb_exception catch_exception (struct ui_out *uiout, |
| catch_exception_ftype *func, |
| void *func_args, |
| return_mask mask); |
| |
| /* If CATCH_ERRORS_FTYPE throws an error, catch_errors() returns zero |
| otherwize the result from CATCH_ERRORS_FTYPE is returned. It is |
| probably useful for CATCH_ERRORS_FTYPE to always return a non-zero |
| value. It's unfortunate that, catch_errors() does not return an |
| indication of the exact exception that it caught - quit_flag might |
| help. |
| |
| This function is superseeded by catch_exceptions(). */ |
| |
| typedef int (catch_errors_ftype) (void *); |
| extern int catch_errors (catch_errors_ftype *, void *, char *, return_mask); |
| |
| /* Template to catch_errors() that wraps calls to command |
| functions. */ |
| |
| typedef void (catch_command_errors_ftype) (char *, int); |
| extern int catch_command_errors (catch_command_errors_ftype *func, char *command, int from_tty, return_mask); |
| |
| #endif |